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1.
The human visual system is amenable to a number of adaptive processes; one such process, or collection of processes, is the adaptation to blur. Blur adaptation can be observed as an improvement in vision under degraded conditions, and these changes occur relatively rapidly following exposure to blur. The potential important future directions of this research area and the clinical implications of blur adaptation are discussed. 相似文献
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4.
E Flescher M J Dauphinée D Fossum J Ledbetter N Talal 《Arthritis and rheumatism》1992,35(9):1068-1074
OBJECTIVE. To study the effects of a novel A-type retrovirus, detected in cocultures of lip biopsy specimens from Sj?gren's syndrome (SS) patients and a human T cell line, on the infected T cells. METHODS. Interleukin-2 (IL-2) and IL-6 secretion were measured by bioassay and enzyme-linked immunosorbent assay, respectively, in the infected and noninfected cell lines. Surface antigen expression was determined by flow cytometry, using monoclonal antibodies. Protein kinase C (PKC) activity was measured using an enzyme assay kit, and calcium mobilization was assessed with a fluorescent probe. RESULTS. Infected cells expressed less CD4 and IL-6 receptor, but more HLA-DR, compared with noninfected cells. Infected cells also produced less IL-2 and displayed reduced PKC activation and calcium mobilization. A similar defect in calcium mobilization was detected in T cells from SS patients. CONCLUSION. These data suggest a possible involvement of the newly described retrovirus in T cell abnormalities. 相似文献
5.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
6.
N Talal 《Bulletin on the rheumatic diseases》1991,40(6):6-8
HIV infection can produce a clinical syndrome and immunologic changes similar to those seen in SS. HIV infection can occasionally result in an SS-like disease but without the formation of antibodies to Ro(SS-A) or La(SS-B). Could this mean that a retrovirus yet to be discovered is responsible for the autoimmune exocrinopathy known as SS? Evidence to date is circumstantial, based on antibodies to a retroviral protein (p24). The idea that retroviruses act in a genetically susceptible host to cause SS is a reasonable hypothesis. Syphilis and Lyme disease are both models where infectious organisms cause chronic multi-system disease. The virus of SS need not be a foreign invader but could be an endogenous retrovirus contained within our own genetic material (10, 11). More investigation is needed to exploit the research opportunities that have appeared in clinical immunology since the AIDS epidemic first appeared. 相似文献
7.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
8.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14
9.
R Goldblum R Pillarisetty M J Dauphinee N Talal 《Clinical and experimental immunology》1975,19(2):377-385
Chronic graft-versus-host (GVH) disease was induced in NZB/NZW F1 (B/W) hybrid female mice by the weekly injection of parental NZB spleen cells. Control mice received injections of syngeneic spleen cells only. The mice were assayed for antibodies to [3H]DNA and [3H]polyadenylic-polyuridylic acid by a cellulose ester filter radioimmunoassay, and for antibody to thymocytes by a cytotoxicity method. GVH disease accelerated the development of all three antibodies in B/W mice. In addition, sucrose density gradient ultracentrifugation of pooled sera suggested that an accelerated switch from 19S to 7S anti-DNA production may be an early effect of GVH. The mechanism of acceleration is discussed in terms of immunological and viral factors generated by the GVH reaction. 相似文献
10.
Metabolic adaptation of the chick embryo to chronic hypoxia 总被引:1,自引:0,他引:1